Bio-Inspired Retinal Implants | Richard Taylor | WINGS

Richard: Good evening. So when President Schill first arrived Eugene I had a meeting with him and he said,
“You know Richard? I want you to think big. And I want you to put some pretty big requests
into me,” And so I thought a little moment, I thought well I’ll a joke I said, “Could
you organize a solar eclipse in Oregon.” I didn’t realize he was actually going to do it. Thank you Michael. Did anyone see it? So scientifically in a way, it’s quite trivial. You know one object moved in front of another
and block the light. As simple as that. Right? But when you see something like that with
your own eyes then, and we all remember that like, really awe-inspiring moment when we feel that
deep connection with the universe that we live in. And that’s what our vision gives to us. Now got to work how this thing works. It’s not that, Dave did you hand me the right
thing? Green is good, all right. Cool. Imagine now though if all that you saw was
just inky blackness, all of the time. You know imagine the loss day of the day. So tonight, I want to firstly emphasize just
what a gift our human vision is to us. And I also want to tell you about our plans
to restore vision to those who’ve lost this gift. So let’s start at the start, a very simple thing. Light comes in through a window at the front
of the eye and then a lens focuses it on a screen at the back and the screen is composed
of these little light detectors called photoreceptors. So each photoreceptor receives light and converts
it to an electrical signal and then that signal is passed to the brain along your
body’s electrical wiring. What we call the neurons. So this black pupil is the window that lets
the light in, and then the iris surrounding it controls the size of the window. But the iris also serves an aesthetic function. Its name is actually derived from Greek mythology
and it means the goddess of the rainbow. Now early humans all have brown, eyes blue
eyes only emerged as recently as 5000 years ago. So next time you get a chance, just marvel
at all of those subtle little color variations in your own personal rainbow because it’s
a recent development in our human adventure. Now looking in through that window you can
see it’s dark in there and that’s a good thing. It means that all of the light has been absorbed
by those little photoreceptors on the back screen. Let’s have a look at those. I always think that they look like a vegetable
garden, right? But they’re a very small vegetable garden. Each photoreceptor is about a million times
smaller than a meter. And they’re that small, so you can cram 126 million
of them into each eyeball, because just like your digital camera, the more pixels the better
the image that you’re gonna get out. This is the electrical wiring in the screen
at the back, so all of those intricate connections form an electric circuit that process and
enhance the signal so you see more clearly. For example these two circles on the left
and right, in reality, they are exactly the same color. They looked different because they’re being
processed by this electric circuit. Then this enhanced signal gets sent off to
your brain. Every second your eyes bombard your brain
with 2 billion pieces of information, the whole of the rest of your body combined sends
less than half that amount to your brain. So right now that’s what’s happening to your
brain your eyes are bombarding it with all of this information and to cope with it, a
third of your brain is dedicated to vision. Now the music lovers out there are always
surprised and I think a little disappointed to learn that hearing only gets 3 percent
of your brain so vision gets ten times more than your hearing. Vision is your primary sense and you can see
that in the phrases we use. “I see what you mean.” We equate seeing with meaning, right? You just used your vision to sense the magnificence
of this self-portrait for example. But vision gives us more than knowledge. It also allows us to appreciate beauty, and
nature’s beauty, and its impact on us is profound. For example, patients recovering from major
surgery recover far more quickly if they’re given a window looking out on nature’s beauty. But what is it about nature that makes it
so beautiful. Well, typical natural scenes, like this one
of the Cascades, are composed of what are called fractal patterns. And fractals are simply patterns that repeat themselves at different magnifications. So a great example is, are trees. You have a big branch that splits into smaller
branches, that splits into smaller branches, that splits into even smaller branches. The same rivers. Mountains are fractals. You have these big peaks, sat on top of those
smaller peaks, sat top of those even smaller peaks. Clouds are fractal, you have bumps upon bumps,
upon bumps. So when you’re starting out at nature, you’re
actually staring out at fractal patterns and through evolution, your visual system has adapted
to process these fractal patterns with ease, and that’s called fractal fluency. Your eye has become fluent with this natural
language of fractals. And our research shows that this fractal fluency is occurring at many different stages of the visual system. All the way from the way that your eyes move,
through to which parts of the brain get activated. Our research also shows that it’s this fractal
fluency that is inducing this profound expertic experience which causes your body to relax
by up to 60 percent. So when someone loses their vision, not only
do they lose this primary sense for acquiring information, they also lose this calming connection
with nature’s beauty. Now there is 39 million people around the
world who are totally blind, many of them since birth, and then there’s another 246 million
people who suffered vision loss to the extent that it severely impacts their daily activities. Now we’ve all met people who’ve been blind
from birth and they can do astonishing things. In a way, blindness is a part of who they
are and they may not even be interested in technology that could give them vision. But what about the other 246 million people
who’ve had vision? They rely on it, and then they lose it. They will want it back and they’ll want it back
desperately. Now your photoreceptors, those little light
detectors on the back screen, they are absolutely vital. If you damage those, that will lead to a blind
spot in your vision. For example, all of those little silver points that they are healthy
photoreceptors and that dark crescent region. That’s a region where they’ve been damaged. That was caused by someone looking directly
at the eclipse without the appropriate safety spectacles. So just 20 seconds staring directly at the
sun is enough to damage those photoreceptors. So don’t do it, right? They are that sensitive. Now unfortunately, in addition to accidents,
there are also diseases that also attack your photoreceptors, for example, macular degeneration
shown on the left. Retinitis pigmentosa, shown on the right. And currently there are no conventional cures
for the most common forms of these diseases and they are progressive. So one day you’ll notice a blind spot, and
then through the course of time, and it might take weeks or decades depending on the disease,
this blind spot will grow and grow and gradually reduce the official gateway to everything
that you know and love. Now, most people don’t realize that blindness
is quite prevalent. For example, let’s say that we all want to
live beyond 80 right. That’s a good plan, and it’s likely, what
people don’t tell you is that means that you’ve got 25 percent chance of getting macular degeneration. So that’s one in four of us in the room right
now and that’s just one disease. Does anybody want any good news?
Good news is that we’re in an era where science is coming to the rescue with a number of
strategies, one of which is bionic eyes. I’ve been interested in bionic eyes for a
long time. I can tell some of you know who this is. This is my hero, The Six Million Dollar Man. As a little kid, I was a big fan of science
fiction. The Six Million Dollar Man was an astronaut who was rebuilt after a crash and
he was given a bionic eye. Now although it is written in the early ’70s
it was based around about now and the writers assumed that by now a bionic eye would be
vastly superior to our natural eye. The reality is, we’re not even close and that’s
not through lack of trying. It’s because through evolution nature has
given you this amazing visual system that’s very hard to replicate. Now when I tell my undergraduate students
it’s hard to build a bionic eye they look skeptical. They get out their cell phones and say, “Look, look this cell phone has got a great camera. Richard, haven’t you thought about just putting
that camera in the eye,” Oh, helpful suggestion because really you can now get digital sensors
that have as many pixels as your eye does. But, the bionic eye faces a challenge that
the camera doesn’t it – has to pass its electrical signal into the body’s wiring to get it to
the brain and that’s the challenge. So what do we know about passing electricity
into the body? Alright. Well, we’ve all heard of the horrors of a
Frankenstein’s monster, right, so we’re not going to do that. But what some people don’t realize is that
that science fiction was actually inspired by science fact. There was a French physician called Charles
Le Roy who told his patients to close their eyelids, get ready for this, and when they
close their eyelids he whips out two electrodes and zapped their eyeballs with bolts of electricity. After they’d recovered from the surprise,
they reported that they’d seen flashes of light and this is what happened. So there’s a neuron and like we said earlier
the neurons string together to form a wire that carries the signal from the eye to the
brain. La Roy’s electrode had come in and induced a signal in that middle neuron which passed it to the brain, but the brain assumed that the signal had come all the way from the photoreceptors in the eye ,and so interpreted it as a flash of
light. So that means then that we can build implants
with arrays of artificial photoreceptors where each receptor receives light, converts
it to an electrical signal, and then just like La Roy’s electrodes, it can pass the signal
into the neurons and off to the brain. But we do have to get the electronics right. If you open up your computer, or your digital
camera, or your cell phone you will find conventional electronics that look like this and that is
radically different from your body’s wiring. Your neurons are fractals, featuring branches
that repeat at many different magnifications. So at the U of O we’re building these bio-inspired
electronics, shown on the left, that copy the fractal branches of the neurons, shown
on the right. With the idea that the neurons will interpret
our electronics as being another fellow neuron rather than a foreign device. And our research shows that enhanced communication
could restore sight to over a million people. So statistically then that’s at least one
person in this room, which will obviously be quite an honor if we can do that. But remember this, as shown by these simulations, an implant vision will never be as good
as your natural vision. It will never be as good as this gift that
nature is giving you for free. And this is how many times you’ve used that
gift in just a short presentation. So thank you for watching. Thank you. [Applause]

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